Novo Nordisk's hopes of heralding a new era of obesity treatment with its next-generation CagriSema drug may be in doubt after a series of trial results have left investors feeling unsatisfied.

Novo Nordisk agreed to pay up to $2 billion for the rights to a developmental weight-loss and obesity drug from Chinese pharmaceutical company The United Bio-Technology Co., as it looks to boost its pipeline of next-generation drugs.

Danish drugmaker Novo Nordisk has bought global rights to China-based United Laboratories International's so-called "triple-G" weight-loss drug candidate in a deal worth up to $2 billion.